There is in widespread use a plywood forming system, here referred to as the “1⅛″ plywood forming system”. This system consists of 1⅛″ thick plywood panels, typically 24″ wide by 8 feet high, reinforced with ¼″×2″ steel straps secured horizontally at regular intervals, to the ends of which are attached swinging steel latches which interconnect the individual panels into a continuous wall and also secure the flattened wire snap ties which hold the opposing panel wall assemblies in position against the hydrostatic force of the liquid concrete.
The panel latches are pivotally attached to the ends of the ¼″×2″ steel straps, herein called form panel bars, with hex head shoulder bolts, herein called panel bolts, and engage a similar bolt in the adjoining panel. Additionally, an extra bolt is usually applied to said form panel bars, which is available for attaching various brackets and stiffeners.
It is frequently desired to attach horizontal stiffening members, or walers, to the outside faces of the plywood form panels. These walers commonly consist of a 2″×4″ or 2″×6″ board and are generally held in position against the form by multiple brackets in the general form of a shelf bracket, with a vertical member to keep the waler approximately held against the form panels. Some prior art brackets have incorporated means of pressing the waler against the form panels, using wedges, cams, or other devices. For instance, U.S. Pat. No. 4,508,310 describes a waler, which incorporates an attached wedge, held in a receiving position for the waler by a keeper attached below the body of the waler.